Question

Two bodies having same masses. If ratio of their velocity is 2:3, then find the ratio of their kinetic energy..​

Answer 1

Answer:

4:9 is the coorect answer

Answer 2

Given :

Ratio of the velocities of two masses = 2 : 3

To Find :

Ratio of the kinetic energy of masses

Solution :

The ability of a body to do work due to its speed alone is called Kinetic Energy.

Kinetic Energy (KE) = $\frac{1}{2} mv^2$

as in the given problem, mass of both the bodies are same. So,

Kinetic Energy ∝ (Velocity)²

Therefore,

⇒  $\frac{KE_1}{KE_2}$  = $\frac{V_1}{V_2}$

⇒  $\frac{KE_1}{KE_2}$  =  $(\frac{2}{3} )^2$

∴   $\frac{KE_1}{KE_2}$  = $\frac{4}{9}$

Hence, the ratio of kinetic energies of the body is 4 : 9